Gates are commonly found as either single or double swing or as sliding gates. Single or double swing gates have wings that rotate on hinges that are fixed to fence posts or other parts of fencing. Sliding gates slide along a track or are suspended along the length of the fence. Very rarely do you find gates that lower into a cavity. Such gates move vertically along guide posts that normally extend above ground level. All varieties of gates can be fitted with elements of automation that allow them to be remotely opened and closed. Some of the automation elements are an actuator that is a drive system for the gate and a remote control device that allows the actuators to be activated remotely. The automation elements are fitted with protection devices that safeguard people and property from being accidentally damaged by the operation of the gate drive system.
The inconvenience of swing and sliding gates is the necessity to have appropriately sufficient space in front of the gate or alongside the fence to open the gate, however gates that lower into a cavity do not require this space to operate.
Solutions that are known to technically allow span gates to lower into a cavity in the ground are used for gates that are quite low (up to 1.5 m) and are also not very wide. These type of gates require guide posts that protrude above ground level to a height that is at least the same as the height of the span. Additionally, due to limitations in the space dedicated for the fitment of the actuators that move the span, the actuators have a limited lifting force, and consequently it is not possible to lift spans that have a very large mass. It is not without significance that the majority of existing span gates which lower into a cavity in the ground require access shafts with a ladder to install and maintain the gates, making the emergency operation very difficult if not impossible without a heavy handling equipment. The solutions that have been used in the gates to date do not allow for the use of any type of span that is tailor made to the individual taste of the Customer, neither are they easy to be changed once installed. In the majority of cases, it becomes very complicated to change the existing type of gate (i.e. a swing or sliding gate) to a gate with a span that lowers into a cavity, when the same span is to be reused.